392 Hemi Supercharger Install - Pro Boosted

It’s a nice June Monday, and we’re at an undisclosed location within the building where Procharger builds their intercooled supercharger systems. We’ve snuck in the back door, and readied our camera as two guys (Tyler and Tyler--yep, no kidding), get ready to install the first production-ready supercharger kit on a 392-Hemi powered Challenger. We wanted to be the first to see this new kit, but there was one glitch to us being sneaky about it. Since it’s almost impossible to hide my large-by-huge frame behind the building’s support pole, I was spotted.

2/20<strong>01</strong> Installation of the kit does require some disassembly of the car’s front end. Simple hand tools can accomplish this. Start removing the retaining clips that hold the under hood plastic shield in place.

So, now that we’re out in the open and the guys can see us, we were given permission to follow along as they install this first ever supercharger kit for the 392 Hemi. But, before get to wrenching, we need a little background information. In its simplest form, a supercharger is a device that forces air into the engine. That increase in air also allows an increase in the engine’s fuel-burning capability, resulting in more power. It’s a simple concept, but there really is more to it. We’re not going to get into a complete article about the different styles of superchargers, for now, we’re just going to focus on centrifugal supercharging.

3/20<strong>02</strong> Next comes removal of the undercar splash shield.

With centrifugal supercharging, the supercharger’s impellor is driven by the engine via a drive belt. The supercharger’s pulley that is connected to the drive belt, drives a large gear in the supercharger’s housing that then meshes with a smaller gear. This smaller gear is connected to, and is what drives the impellor. The impellor then pulls air into the supercharger, and forces it into the engine. The size of the gears within the supercharger directly determines the ratio of the supercharger. While boost levels can be altered with pulley changes, the ratio is set. The centrifugal supercharger is generally attached to the front of the engine with a rigid bracket and driven via a belt-drive or gear-drive from the engine’s crankshaft.

4/20<strong>03</strong> Pull a couple of clips, and some screws and the nose comes right off.

So, what does a centrifugal supercharger actually do? Like we said, a centrifugal supercharger contains an impeller that spins at a very high speed. When the air leaves the impeller, it might be traveling at high speed, but at this point, it has very little pressure. This low-pressure, high-speed air is then forced through the diffuser and housing, which compresses the airflow, increasing its pressure. This newly compressed air is then fed into the engine, giving the engine the ability to burn more fuel and have a higher level of combustion. That’s the gist of it anyway.

5/20<strong>04</strong> The kit does require the removal of the power steering reservoir. The kit comes with a new remote reservoir and the required hardware. It’s easier to remove the pump assembly to handle the simple conversion.

Anyway, in regards to the tuning, or lack thereof until now, supercharging a 2011 and new Mopar just wasn’t viable. The computers were locked down, and no aftermarket tuning could be made to the engine management system that would allow the aftermarket to add any performance to these cars. Now that the tuning has been made available, the guys at Procharger are now able to install a supercharger on a new Hemi, and they can also install the required tune to make all work together.

6/20<strong>05</strong> Once the new reservoir is mounted, it looks factory installed.

Let’s be up front about this install: While it can be done by anyone with mechanical capabilities, it’s not a task to be taken lightly. When you open the box, you’ll see that there are a lot of parts, and Procharger makes every attempt to make sure that every kit includes everything needed. If you feel comfortable installing it yourself, figure on a weekend. If you decided to have one of Procharger’s dealers install the kit, that’s fine also, at least this article gives you some insight into what it takes.

7/20<strong>06</strong> The factory over flow container also needs to be replaced, as it is directly located where the supercharger needs to go. The Procharger kit comes with this aluminum container and the required hoses for connection.

Intercooled ProCharger System: *Starting at $6,000

*starting price varies by dealer.

Stay Cool

Cooler air makes more power--period. The problem with getting a cool, dense charge of air from a supercharger is that when you compress air, you also heat it. To overcome this heated air concern, you need to cool the air before it gets to the intake of the engine. Procharger adds an intercooler for what is called air-to-air intercooling. On street cars, air-to-air intercooling is accomplished by locating the intercooler at the front of the vehicle where it gets a constant supply of airflow. How it works is: compressed air is drawn in one side of the intercooler, making its way into the intercooler. Once inside, the compressed air is cooled by the airflow moving through the intercooler (like air through a radiator). This cooler air is then routed into the throttle body and into the engine.

8/20<strong>07</strong> Since more air will be forced into the engine, more fuel is also a requirement. Larger fuel injectors are supplied, and install easily.

Centrifugal Supercharger Components

Impeller

The impeller is what actually pulls the air into the supercharger. The impeller then pushes the air into the blower, building the pressure known as boost.

Compressor Housing (also known as Volute)

The snail-shaped design of the compressor housing is a trait unique to centrifugal superchargers. The housing’s purpose is to deliver the compressed air to the engine. This is done through some kind of piping system. Aluminum is typically used for supercharger housings, due to the combination of strength, weight, and resistance to corrosion.

9/20<strong>08</strong> By reading the instructions, the brackets are installed next. The kit from Procharger is available in either a satin or polished finish.

10/20<strong>09</strong> Once the brackets are in place, the supercharger can then be installed. The supercharger is self-contained, meaning that no plumbing of oil lines needs done. Once the unit is installed, it’s filled with oil and ready to go.

11/20<strong>10</strong> You’ve added an accessory, so you need to add belt length. The belt comes with the kit, and can be replaced through any parts store if need be. The factory tensioner is retained, but will be relocated to the supercharger’s bracket. Again, full instructions come with the kit.

Diffuser

Downstream of the impeller, directly in the flow path of the air is what’s called the diffuser, it is the diffuser’s job to increase the pressure of the incoming air by gradually slowing (diffusing) its velocity .

12/20<strong>11</strong> A MAP sensor change will also be required. From the factory, your car came with a one-bar MAP sensor. This only senses manifold pressure (or vacuum), up to 14.7 psi (one bar of pressure), such as would be in a normally aspirated engine (no boost). So, a two-bar sensor measures from negative 14.7psi (or so) to 0 psi, and then from 0 psi to 14.7 psi.

13/20<strong>12</strong> One key element to the Procharger kit is it’s intercooler. Cooling the air makes it denser, which makes more power. Installing the intercooler was the main reason that the nose of the car needed removed to facilitate the install in front of the radiator, but behind the grille.

14/20<strong>13</strong> Once the intercooler is installed, it’s time for some plumbing. The kit has all of the piping required to plumb from the supercharger to the intercooler, and ultimately to the throttle body. If you’re wondering why the Procharger kit uses an open element air filter mounted under the hood instead somewhere away from the engine, they tell us that they have done testing to verify that the routing of the incoming air charge has more of a bearing on power than the under hood temperature.

Transmission

The transmission is the gear set that transfers the crankshaft’s energy to spin the impeller. There is a step up ratio built in to the gears, and this makes the impeller spin at a super high speed (30,000 rpm or more). Transmission step up is required so that the impeller speeds are necessary to create the desired boost.